%0 Journal Article
%T Experimental Study of the Interaction between Recrystallization and Precipitation Processes of an AA8011 Commercial Alloy
%A Ney Jos¨¦ Luiggi
%A Mar¨ªa Valera
%A Jes¨²s P. Rodriguez
%A Jos¨¦ Prin
%J Journal of Metallurgy
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/345945
%X Phase changes in a commercial AA8011 alloy from different initial microstructure conditions were studied using thermoelectric power ( ), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM) techniques with the purpose of obtaining evidence of the interaction between recovery-precipitation and recrystallization-precipitation processes occurring during nonisothermal heating at different rates. Thermoelectric power and its thermal derivative reflect this evidence by a displacement of the characteristic precipitation peaks, the recovery and recrystallization contributions remaining masked by the strong incidence of the iron precipitation on that property, while DSC measurements detect the emergence of new peaks not observed on thermograms of homogenized samples. An exhaustive study of these peaks permits direct differentiation between precipitation and recovery-recrystallization contributions. TEM confirms the interaction between both processes by means of local observations. 1. Introduction The study of the interaction that occurs between phase precipitation process and recrystallization in deformed materials is a topic of great interest in materials science because this interaction regulates the kinetics of growth of new grains and the formation of phases in the material. The combination of both effects certainly leads to modifications of the physical and mechanical properties of the material. A plastically deformed material shows a great amount of internal strains, mainly as dislocations, which store part of the energy transferred to the crystal during deformation, the reordering of which helps release said energy. Many mechanisms contribute to that end, where the recovery and recrystallization processes recover and lead to the appearance of new grains through the release of stored energy, the evolution of the recrystallization occurring in a collective manner by nucleation and growth [1¨C6]. The diffusive process conducive to the phase transformation also takes place at the same temperature ranges where recrystallization occurs, both processes being regulated by the starting microstructure. Schematically, both a possible evolution of the atomic supersaturation after quenching of a homogenized sample as a function of aging time at a temperature below the solubility limit and the evolution of the density of internal strain as a function of the degree of deformation by rolling in homogenized and quenched samples are shown in Figure 1. Immediately after quenching at a temperature below the solubility limit, the homogenized
%U http://www.hindawi.com/journals/jm/2014/345945/